Thieno[2,3-C]Pyrrole-dione derivatives and their use for organic semiconductors

ABSTRACT

Compounds of formulae (I) and (II) useful as organic semiconductor materials, and semiconductor devices containing such organic semiconductor materials are described.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is the US national stage of International PatentApplication PCT/IB2013/060162 filed internationally on Nov. 15, 2013which, in turn, claims priority to Italian Patent Application No.MI2012A001952 filed on Nov. 16, 2012.

The present invention relates to a novel n-type organic semiconductormaterial, and semiconductor devices containing said n-type organicsemiconductor material.

It is known that organic semiconductors are materials into which chargecan be reversibly introduced by the application of electromagneticenergy or chemical dopants. The electronic conductivity of thesematerials lies between that of metals and insulators, spanning a broadrange of 10⁻⁹ to 10³ Ω⁻¹ cm⁻¹. As in traditional inorganicsemiconductors, organic materials can function either as p-type orn-type. In p-type semiconductors the majority carriers are holes, whilein n-type the majority carriers are electrons.

The vast majority of the prior art has focused on the design, synthesis,and structure-property relationships of p-type organic semiconductormaterials, including: oligoacenes, fused oligothiophenes,anthradithiophenes, carbazoles, oligophenylenes, and oligofluorenes,some of which have resulted in field-effect transistors with performancesuperior to amorphous silicon. In contrast, the development of n-typeoligomer and polymer semiconductors has lagged behind p-type materials.In fact, compared to the p-type semiconductors, n-type semiconductorsare still not fully developed, and the performances are notsatisfactory.

Organic semiconductors that possess a high electron affinity are howeveralso required, as both p- and n-channel materials are required forefficient logic circuits and organic solar cells. Indeed, n-type organicfield-effect transistors are envisioned as key components of organic p-njunctions, bipolar transistors, and complementary integrated circuitsleading to flexible, large-area, and low-cost electronic applications.

A variety of organic semiconductors have been considered in the art asn-type organic semiconductor materials.

Aromatic tetracarboxylic anhydride and their diimide derivatives werereported among the first n-channel materials. Among the materials ofthis class, perylenetetracarboxylic diimides having fluorinated sidechains showed mobilities up to 0.72 cm²V⁻¹ s⁻¹, which only slightlydecreased upon air exposure. Air stability, packing grain size andmorphology of the deposited films as well as electrical performance canbe altered by varying side-chain length, insertion of oxygenated groupsand degree of fluorination. However, most of the perylene buildingblocks, due to the structural rigidity and moderate solubility, do notallow readily structural changes limiting the volume of materialsaccessible.

Other classes of n-type organic materials have been described such ascyanovinyl oligomers, fullerenes.

J. Am. Chem. Soc. 2009, 131, 16616-16617 describes ambipolar chargetransport properties of diketopyrrolopyrrole-copolymers.

A benzothiadiazole-diketopyrrolopyrrole copolymer described in Mater.2010, 22, 47, 5409-5413, shows high and balanced hole- and electronmobilities of 0.35 cm²V⁻¹s⁻¹ and 0.40 cm²V⁻¹s⁻¹, respectively. Largerelectron mobilities values up to 0.85 cm²V⁻¹s⁻¹ were achieved in air forelectron-only transporting n-type polymer, called poly{[N,N9-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,59-(2,29-bithiophene)},(Polyera Activink N2200), in a staggered top gate configuration.

N-type semiconductor materials consisting of oligothiophenes bearingfluorinated side groups have been also described in J. Am. Chem. Soc.2005, 127, 1348 and Angew. Chem. Int. Ed. 2003, 42, 3900. Theseoligomers showed mobilities up to 0.43 cm²V⁻¹s⁻¹. However, OFETs basedon most of these perfluoroaryl and perfluoroalkylaryl substitutedmaterials were unstable in air or suffered from high threshold voltage.Fluorocarbonyl-functionalized oligomers were also described, whichshowed improved air stability, but lower electron mobilities withrespect to fluorinated oligomers.

Oligomers and polymers containing a bithiophene-imide units as innercore have also been described.

For example, J. Am. Chem. Soc. 2008, 130, 9679-9694 describesN-alkyl-2,2′-bithiophene-3,3′-dicarboximide-based homopolymers andcopolymers showing p-type or n-type semiconductor behavior depending onthe polymeric structure. However, no air-stable devices could beachieved with such materials. In addition, the poor reactivity of thestarting dihalogenated bithiophene-imide compounds limits theaccessibility of this class of materials.

J. Am. Chem. Soc. 1998, 120, 5355-5362, Tetrahedron Letters 44(2003)1653-1565 disclose copolymers containing electron poor3,4-imido-thienyl blocks alternated to electron rich amino substitutedthienyl blocks. No investigation was performed regarding the electricalproperties of such copolymers.

N-alkylated poly(dioxopirrolothiophene)s are described in OrganicLetters 2004, 6, 19, 3381-3384. However, no proof of an efficient n-typebehavior in OFET devices is reported.

Each of the afore mentioned class of materials has poor electricalperformances.

WO2008/127029 relates to dioxypirrolo-heterocyclic compounds having thepyrrole moiety fused to the 3,4 position of the thienyl ring and organicelectronic devices using said dioxypirrolo-heterocyclic compounds.

Wei Hong et al, “Linear fused dithieno[2,3-b: 3′2′-d]thiophene diimides”Organic Letters, vol 13, no. 6, 18 Mar. 2011, pages 1420-1413, disclosesa class of linear fully fused dithieno thiophene diimides.

The documents: DE1954550; Ronova Iga A et al: “The effect ofconformational rigidity on the initial decomposition temperature of someheterocyclic polyimides”, High Performance Polymers, Institute ofPhysics Publishing, Bristol GB, vol. 14, No. 2, 1 Jan. 2002, pages195-208; and Gaina C. et al, “Polyimides containing 1,4-dithiine unitsand their corresponding thiophene 2,3,4,5 tetracarboxylimide units” HighPerformance Polymers, Institute of physics publishing, Bristol GB, vol.11, No. 2, 1 Jun. 1999, pages 185-195, disclose polymeric diimidecompounds in which the member connecting the polymer repeating units isthe N-imidic substituent. The three last cited documents do not mentionany semiconductor property of the compounds therein disclosed.

WO2006/094292 discloses thienopyridine compounds capable of modulatingthe stability and/or activity of hypoxia inducible factor,pharmaceutical compositions comprising said compounds and chemicalintermediates useful for preparing said compounds. Among said chemicalintermediates, specific compounds having a4,6-dioxo-thieno[2,3-c]pyrrole nucleus are disclosed.

EP0467206 discloses specific compounds having a4,6-dioxo-thieno[2,3-c]pyrrole nucleus and their use as herbicide.

However, WO2006/094292 and EP0467206 do not teach the semiconductorproperties of said compounds.

Therefore, there is still the need of n-type organic semiconductormaterials or compounds that possess higher electron mobility properties.

In the present specification and in the claims, the term “n-type organicsemiconductor” means a material that, inserted as active layer in afield effect device architecture with a source, a drain and gate controlelectrodes, shows an electron mobility higher than 10⁻⁷ cm²V⁻¹s⁻¹.

It is an object of the present invention to provide new organicmaterials suitable for use as semiconductor material, which is free fromsaid disadvantages. Said object is achieved with compounds whose mainfeatures are disclosed in the first claim, a use of said compounds whosemain features are disclosed in claim 10 and an electronic device whosemain features are disclosed in claim 12. Other features of saidcompounds are disclosed in claims 2 to 9.

Advantageously, the compounds according to the present invention may beuseful as p-type, n-type or ambipolar organic semiconductor material.

Particularly, the compounds according to the present invention possesshigh electron mobility properties, excellent stability under atmosphericconditions and are accessible through synthetically easy processes.

Further advantages and features of the compounds, materials and devicesaccording to the present invention will become clear to those skilled inthe art from the following detailed and non-limiting description of anaspect thereof with reference to the attached drawings, wherein:

FIG. 1 are UV-vis and emission spectra of a compound according to thepresent invention;

FIGS. 2 a) and b) are DCS thermograms of the compound of FIG. 1;

FIGS. 3 a) and b) are lucous curves and output curves of a thin filmtransistor obtained with a compound of FIG. 1;

FIG. 4 is a transfer saturation curve N type of a thin film transistorobtained with a compound of FIG. 1;

FIGS. 5a ) and b) is a transfer saturation curve P type of a thin filmtransistor obtained with a compound of FIG. 1.

According to an aspect of the present invention, a compound of formula(I) or (II) is provided:

wherein:

R¹, R², R³ independently of each other, are selected in the groupconsisting of hydrogen, C₁-C₄₀ linear or branched alkyl groups, C₂-C₄₀linear or branched alkenyl groups, C₂-C₄₀ linear or branched alkynylgroups, C₁-C₄₀ linear or branched heteroalkyl groups, C₂-C₄₀ linear orbranched heteroalkenyl groups, C₂-C₄₀ linear or branched heteroalkynylgroups, C₃-C₄₀ linear or branched cycloalkyl groups, C₂-C₄₀ linear orbranched heterocycloalkyl groups, C₂-C₄₀ linear or branchedalkylcarboxylic groups, C₂-C₄₀ linear or branched alkylcarboxamidegroups, C₂-C₄₀ linear or branched alkylimino groups, C₁-C₄₀ linear orbranched alkylsulphonic groups, C₁-C₄₀ linear or branched nitrilegroups, C₆-C₅₀ unsubstituted and substituted monocyclic aryl groups,C₁₀-C₅₀ polycyclic aryl groups, C₁₀-C₅₀ substituted polycyclic arylgroups, C₁-C₅₀ unsubstituted and substituted monocyclic heteroarylgroups, C₆-C₅₀ polycyclic heteroaryl groups, C₆-C₅₀ substitutedpolycyclic heteroaryl groups;

R⁴ and R⁵, independently of each other, are selected in the groupconsisting of hydrogen, halogens, C₁-C₂₀ linear or branched alkylgroups, C₂-C₂₀ linear or branched alkenyl groups, C₂-C₂₀ linear orbranched alkynyl groups, C₁-C₂₀ linear or branched heteroalkyl groups,C₂-C₂₀ linear or branched heteroalkenyl groups, C₂-C₂₀ linear orbranched heteroalkynyl groups, C₃-C₂₀ linear or branched cycloalkylgroups, C₂-C₂₀ linear or branched heterocycloalkyl groups, C₂-C₂₀ linearor branched alkylcarboxylic groups, C₂-C₂₀ linear or branchedalkylcarboxamide groups, C₂-C₂₀ linear or branched alkylimino groups,C₁-C₂₀ linear or branched alkylsulphonic groups, C₁-C₂₀ linear orbranched nitrile groups,

Ar, Ar¹, Ar², Ar³ and Ar⁴, independently of each other, are moietiesselected in the group consisting of a C₆-C₅₀ unsubstituted andsubstituted monocyclic aryl groups, C₁₀-C₅₀ polycyclic aryl groups,C₁₀-C₅₀ substituted polycyclic aryl groups, C₁-C₅₀ unsubstituted andsubstituted monocyclic heteroaryl groups, C₆-C₅₀ polycyclic heteroarylgroups, C₆-C₅₀ substituted polycyclic heteroaryl groups and combinationsthereof as dimers, trimers and tetramers;

Z and Z′, independently of each other, are selected in the groupconsisting of the bivalent radicals selected in the groups consisting ofthe formulas (III), (IV), (V), (VI), (VII), (VIII), (IX), (X):

wherein G is selected among hydrogen, halogens, C₁-C₂₀ linear orbranched alkyl groups, C₂-C₂₀ linear or branched alkenyl groups, C₂-C₂₀linear or branched alkynyl groups, C₁-C₂₀ linear or branched heteroalkylgroups, C₂-C₂₀ linear or branched heteroalkenyl groups, C₂-C₂₀ linear orbranched heteroalkynyl groups, C₃-C₂₀ linear or branched cycloalkylgroups, C₂-C₂₀ linear or branched heterocycloalkyl groups, C₂-C₂₀ linearor branched alkylcarboxylic groups, C₂-C₂₀ linear or branchedalkylcarboxamide groups, C₂-C₂₀ linear or branched alkylimino groups,C₁-C₂₀ linear or branched alkylsulphonic groups, C₁-C₂₀ linear orbranched nitrile groups, C₆-C₅₀ unsubstituted and substituted monocyclicaryl groups, C₁₀-C₅₀ polycyclic aryl groups, C₁₀-C₅₀ substitutedpolycyclic aryl groups, C₁-C₅₀ unsubstituted and substituted monocyclicheteroaryl groups, C₆-C₅₀ polycyclic heteroaryl groups, C₆-C₅₀substituted polycyclic heteroaryl groups and combinations thereof;

T and T′ are selected in the group consisting of C₁-C₂₀ linear orbranched alkyl groups, C₂-C₂₀ linear or branched alkenyl groups, C₂-C₂₀linear or branched alkynyl groups, C₁-C₂₀ linear or branched heteroalkylgroups, C₂-C₂₀ linear or branched heteroalkenyl groups, C₂-C₂₀ linear orbranched heteroalkynyl groups, C₃-C₂₀ linear or branched cycloalkylgroups, C₂-C₂₀ linear or branched heterocycloalkyl groups, C₂-C₂₀ linearor branched alkylcarboxylic groups, C₂-C₂₀ linear or branchedalkylcarboxamide groups, C₂-C₂₀ linear or branched alkylimino groups,C₆-C₅₀ unsubstituted and substituted monocyclic aryl groups, C₁₀-C₅₀polycyclic aryl groups, C₁₀-C₅₀ substituted polycyclic aryl groups,C₁-C₅₀ unsubstituted and substituted monocyclic heteroaryl groups,C₆-C₅₀ polycyclic heteroaryl groups, C₆-C₅₀ substituted polycyclicheteroaryl groups and combinations thereof;

s is 0 or 1;

n, m, r and t, independently of each other, are integers between 1 and50;

q and f, independently of each other, are integers between 1 and 10; and

p is an integer between 0 and 5.

In the present description and in the claims:

-   -   a “heteroalkyl group” is intended to include, for example, a        halogenoalkyl group, a hydroxyalkyl group, a alkoxyalkyl group;    -   a “heteroalkenyl group” is intended to include, for example, a        halogenoalkenyl group, a hydroxyalkenyl group, a alkoxyalkenyl        group;    -   a “heteroalkynyl group” is intended to include, for example, a        halogenoalkynyl group, a hydroxyalkynyl group, a alkoxyalkynyl        group.

In formulas (VII); (VIII); (IX) and (X), P is phosphor and N isnitrogen.

The value of p is preferably 0, 1 or 2.

The value of q and f, independently of each other, is preferably between1 and 5; more preferably q and f are 1 or 2; even more preferably q andf are 1.

The values of n, m, r and t are preferably comprised between 2 and 50,more preferably between 2 and 30, even more preferably between 2 and 10.

When p assumes the values of 0, then n is particularly preferablycomprised between 2 and 50, more preferably between 2 and 30, even morepreferably between 2 and 10.

According to an embodiment of the invention, s is 0 and p is 1 or 2.

According to another embodiment of the invention, s is 0, p is 1 or 2and n, q, f, m are 1.

Preferably, G is selected in the group consisting of hydrogen, bromine,chlorine, iodine, methyl, ethyl, vinyl, propyl, i-propyl, allyl,propenyl, hexyl, methoxyl, ethoxyl, hexyloxyl, ethylamine, butylamine,hexylamine.

In formula (V) and (VIII) the two G groups and/or the G group and one ofthe T/T′ group may also be connected to form together with the doublebond, a cycle, for example cyclohexene, cyclopentene, dihydropyrrole,phosphranylidene as shown in the following formulas (Va), (Vb), (Vc)that are specific embodiments of formula (V), and formula (Villa) whichis a specific embodiment of formula (VIII):

In an embodiment of the present invention, the groups Z and Z′ areselected in the group consisting of ethynylene cis-ethenylene andtrans-ethenylene.

Preferably, R⁴ and R⁵ are hydrogen.

Preferably, according to the present invention, R¹, R² and R³ areselected in the group consisting C₁-C₈ alkyl groups, C₂-C₈ alkenylgroups, C₂-C₈ alkynyl groups, phenyl group, substituted phenyl groups,benzyl group, substituted benzyl groups.

Preferably, according to the present invention Ar, Ar¹, Ar², Ar³ andAr⁴, independently of each other, are selected in the group consistingof a C₆-C₂₀ unsubstituted and substituted monocyclic aryl groups,C₁₀-C₂₀ polycyclic aryl groups, C₁₀-C₅₀ substituted polycyclic arylgroups, C₁-C₂₀ unsubstituted and substituted monocyclic heteroarylgroups, C₆-C₂₀ polycyclic heteroaryl groups, C₆-C₂₀ substitutedpolycyclic heteroaryl groups and combinations thereof as dimers, trimersand tetramers

The preferred substituents of said monocyclic aryl groups, polycyclicaryl groups, monocyclic heteroaryl groups, polycyclic heteroaryl groupsof Ar, Ar′, Ar^(e), Ar³ and Ar⁴, are selected among halogens, alkyl,alkenyl, alkynyl or heteroalkyl groups. More preferably, saidsubstituent groups are selected in the group consisting of linear orbranched C₁-C₁₂ alkyl, linear or branched C₂-C₁₂ alkenyl, linear orbranched C₂-C₁₂ alkynyl, C₁-C₁₂ perfluoroalkyl, C₁-C₁₂ oxyalkyl, C₁-C₁₂aminoalkyl, C₁-C₁₂ thioalkyl, C₁-C₁₂ haloalkyl, C₂-C₁₂ carboxyalkylgroups, C₁-C₁₂ silicioalkyl groups.

According to an aspect of the present invention, the compounds offollowing formulas (Ia) and (IIa) are provided, which correspond tothose of formulas (I) and (II), wherein p is equal to 0:

wherein R¹, R², R⁴, R⁵, Ar, Ar¹, Ar⁴, Z, f, n, m are as above defined.

In the present description and in the claims, the curved lines informulas (I), (Ia), connecting the Ar moiety to the thieno(bis)imideunit, indicate that said Ar moiety forms a fused ring system with saidthieno(bis)imide unit.

In addition, as usual in chemical drawing practice, in the presentdescription and in the claims the bond lines crossing the thiophenedouble bond in formulas (II), (IIa), indicates that the (Ar¹)_(n) and(Ar⁴)_(m) moiety may be bound to any of the 2 or 3 position in thethiophene rings and are not fused thereto. Preferably, the (Ar¹)_(n) and(Ar⁴)_(m) moieties are bound to the 2 position of the thiophene rings.

In formulas (I) and (Ia), the (Ar¹)_(n) and (Ar⁴)_(m) moieties may bebound to any position of the Ar moiety that is fused to thethieno(bis)imide unit.

In formulas (Ia) and (Ha) the integers n and m are preferably comprisedbetween 1 and 30, more preferably between 2 and 30, even more preferablybetween 2 and 10.

Preferably, in the formulas (Ia) and (IIa), R⁴ and R⁵ are hydrogen and fis 1 or 2.

The compounds according to the invention wherein n is 2 arecharacterized by an advantageously high solubility in a number ofsolvents, for example dichloromethane, dimethyl sulfoxide,tetrahydrofuran, allowing for high level purification and easy solutionprocessing.

Preferably, the Ar¹, Ar², Ar³, Ar⁴, independently f each other, areunits selected among the following groups (a), (b), (c), (d), (e), (f),(g), (h), (i), (l), (m), (n), (o), (p), (q), (r):

wherein A is selected in the group consisting of S, O Se, atoms and SO,SO₂, R¹⁴—P═O, P—R¹⁴, N—R¹⁵, Si(R¹⁵)₂ groups;

D is selected in the group consisting of C, S, O Se, atoms and SO, SO₂,R¹⁴—P═O, P—(R¹⁴), BR¹⁴, N—R¹⁵, Si(R¹⁵)₂ groups;

B, C, independently of each other, are selected in the group consistingof C, N atoms;

E is selected in the group consisting of C(R¹⁵)₂, S, O, and NR¹⁵ group;

R⁸, R⁹, R¹⁰, R¹¹, R¹² and R¹³, independently of each other, are selectedin the group consisting of hydrogen, halogens, C₁-C₂₀ linear or branchedalkyl groups, C₂-C₂₀ linear or branched alkenyl groups, C₂-C₂₀ linear orbranched alkynyl groups, C₁-C₂₀ linear or branched heteroalkyl groups,C₂-C₂₀ linear or branched heteroalkenyl groups, C₂-C₂₀ linear orbranched heteroalkynyl groups, C₃-C₂₀ linear or branched cycloalkylgroups, C₂-C₂₀ linear or branched heterocycloalkyl groups, C₂-C₂₀ linearor branched alkylcarboxylic groups, C₂-C₂₀ linear or branchedalkylcarboxamide groups, C₂-C₂₀ linear or branched alkylimino groups,C₁-C₂₀ linear or branched alkylsulphonic groups, C₁-C₂₀ linear orbranched nitrile groups, C₅-C₄₀ aryl groups, C₆-C₄₀ alkylaryl groups;

R¹⁴, R¹⁵ independently of each other, are selected in the groupconsisting of hydrogen, C₁-C₂₀ linear or branched alkyl groups, C₂-C₂₀linear or branched alkenyl groups, C₂-C₂₀ linear or branched alkynylgroups, C₁-C₂₀ linear or branched heteroalkyl groups, C₂-C₂₀ linear orbranched heteroalkenyl groups, C₂-C₂₀ linear or branched heteroalkynylgroups, C₃-C₂₀ linear or branched cycloalkyl groups, C₂-C₂₀ linear orbranched heterocycloalkyl groups, C₂-C₂₀ linear or branchedalkylcarboxylic groups, C₂-C₂₀ linear or branched alkylcarboxamidegroups, C₂-C₂₀ linear or branched alkylimino groups, C₁-C₂₀ linear orbranched alkylsulphonic groups, C₁-C₂₀ linear or branched nitrilegroups, C₅-C₄₀ aryl groups, C₆-C₄₀ alkylaryl groups.

In formulas (h), (i), (l), (m), (n), (o), (p), (q), (r), it is meantthat the substituent group may be bound to any position of any ringforming the delocalized system.

Examples of the above described groups of formula (a)-(r) are thefollowing:

In other preferred embodiments of the present invention, the Ar¹, Ar²,Ar³, Ar⁴ groups may be a dimer comprising a thiophene, thiazole, furane,benzodithiazole, thienothiophene or phenyl unit that is linked toanother aryl unit, such as the above represented (a)-(r) groups, like inthe following formulas (s) and (t):

wherein W is a moiety selected in the group consisting of the aboveindicated groups (a) to (r), and R¹⁶ is a moiety selected in the samegroup as R⁸-R¹³.

More preferably, the Ar¹, Ar², Ar³, Ar⁴ groups may be a dimer comprisinga thiophene unit that is α-linked to polycyclic or oligoaryl units suchas in the following groups of formula (u), (v), (w), (x) and (y):

wherein R⁸, R⁹ and n have the above described meanings.

In an embodiment of the invention, Ar¹, Ar², Ar³, Ar⁴ are thiopheneunits or substituted thiophene units.

The Ar moiety fused to the thienoimide unit of the compounds of formulas(I) and (Ia) according to the present invention may be advantageouslyformed of one, two or three aromatic rings.

Preferably, in formulas (I), (Ia), Ar is selected in the groupconsisting of the following rings (α), (β), (γ), (δ), (∈), (ζ), (η),(θ), (ι):

wherein X is selected in the group consisting of S, SO, SO₂, O, Si, Se,NR¹⁷,

Y is selected in the group consisting of C and N;

R¹⁷ is selected in the group consisting of hydrogen, C₁-C₂₀ linear orbranched alkyl groups, C₂-C₂₀ linear or branched alkenyl groups, C₂-C₂₀linear or branched alkynyl groups, C₁-C₂₀ linear or branched heteroalkylgroups, C₂-C₂₀ linear or branched heteroalkenyl groups, C₂-C₂₀ linear orbranched heteroalkynyl groups, C₃-C₂₀ linear or branched cycloalkylgroups, C₂-C₂₀ linear or branched heterocycloalkyl groups, C₂-C₂₀ linearor branched alkylcarboxylic groups, C₂-C₂₀ linear or branchedalkylcarboxamide groups, C₂-C₂₀ linear or branched alkylimino groups,C₁-C₂₀ linear or branched alkylsulphonic groups, C₁-C₂₀ linear orbranched nitrile groups, C₅-C₄₀ aryl groups, C₆-C₄₀ alkylaryl groups.

Specific examples of compounds of formula (I) and (II) according to thepresent invention are for example the following synthesized compounds:

Without wishing to limit the present invention to any theory, it isbelieved that the thienoimide moiety, due to its strongelectrowithdrawing effect, can increase the overall electron affinity ofp-conjugated materials promoting the electron charge transportcapability. The presence of the unsaturated bond as linker betweenthienoimide p-conjugated blocks can promotes high solubility, can allowfor the fine tuning of the HOMO-LUMO energy levels, can promote highmolecular planarity thus improved self-assembly and crystallinemorphology, ultimately enhancing the electrical properties and deviceresponses.

On the other hand, the opposite terminal groups may be exploited to tunethe dipole moment, the HOMO LUMO energy levels and orbital distributionand the packing modality, this ultimately influencing the functionalproperties of the resulting materials.

Among the main advantages of such compounds with respect to otherclasses of n-type materials are to be mentioned the easy accessibilityand structural versatility.

The thienoimide moiety can be coupled to selected π-conjugated cores bycross-couplings under conventional or microwave-assisted methods asdescribed below.

The easy accessibility of the compounds according to the invention alsoallows an easy modification of the oligomer size, and degree and type ofmolecular functionalization, which in turn permits application fineproperty-specific design toward the targeted applications.

The compounds according to the present invention can be obtained withelectronic level of purity by chromatography, crystallization andsublimation, with unambiguous molecular structure determination throughclassic analytical methods.

Contrarily to the thiophene-3,4-imide polymers, bithiophene-imidepolymers and perylene tetracarboxylic diimide systems according to theprior art, this class of materials can be prepared with highreproducibility from batch to batch, which is crucial to achieve deviceswith reproducible responses.

According to still another aspect of the invention, it is provided aprocess for the production of a compound according to the invention,wherein the process comprises reiterative halogenation of aromaticcompounds and cross-coupling reactions. The thieno(bis)imide buildingblock can be halogenated or metallated to undergo cross-couplingreactions with aromatic (Ar² or Ar³) and/or unsaturated (Z) basedcounterparts or to dimer of Ar and Z moieties (i.e. Ar²—Z). Theprocesses according to the present invention are preferably catalized bypalladium.

A process for the production of a compound according to formula (Ia) isschematized in scheme 1, whereas scheme 2 shows a possible productionprocess of compounds of formula (IIa):

In schemes 1 and 2, X is an halogen atom, such as Br, I; M is anorganometal compound such as B(OR′)₂ and SnR″₃, wherein R′ is hydrogenor an alkyl moiety and R″ is an alkyl moiety.

In another aspect thereof, the present invention relates to asemiconductor material, comprising at least one compound according toformulas (I) and/or (II). Preferably, said semiconductor materialcomprises at least one compound according to formulas (Ia) and/or (IIa).

In an embodiment thereof, said semiconductor material comprisescompounds 1.

According to another aspect, the invention relates to an electronicdevice comprising a semiconductor layer in contact with a number ofelectrodes, wherein the semiconductor layer includes at least onecompound according to formulas (I) and/or (II). Preferably, saidsemiconductor layer comprises at least one compound according toformulas (Ia) and/or (IIa). More preferably, said semiconductor layercomprises compound 1.

Preferably, said electronic device comprising a semiconductor layerincluding the compounds according to the present invention is selectedamong optical devices, electrooptical devices, field effect transistors,integrated circuit, thin film transistors, organic light-emittingdevices, and organic solar cells.

Particularly, thin films of the thienoimide based materials according tothe invention can be used as active layers in OFETs and OLET devices asdemonstrated in the following examples. They can be used as electron- orhole-transporting layer or ambipolar semiconductor in single layer OFET,as multifunctional electron- and hole-transporting and light emittinglayer in single layer OLET, and as hole or electron transporting layerin multi-layer OLET.

Finally, applications of compounds and materials according to thepresent invention in organic photovoltaics can be envisaged.

In the following examples, all ¹H, ¹³C, spectra were recorded at roomtemperature on a Varian Mercury 400 spectrometer operating at 400 MHz(¹H) and 100.6 MHz (¹³C). Chemical shifts were calibrated using theinternal CDCl₃ resonance which were referenced to TMS.

Mass spectra were collected on an ion trap Finningan Mat GCQspectrometer operating in electron impact (EI) ionization mode. Eachsample was introduced to the ion source region of the GCQ via a directexposure probe (DEP).

Melting points were determined on a ‘hot-stage’ apparatus where themelting process was observed with the aid of a microscope.

UV-Vis spectra were recorded using a Perkin Elmer Lambda 20spectrometer. Photoluminescence spectra were obtained with a PerkinElmer LS50B spectrofluorometer using an excitation wavelengthcorresponding to the maximum absorption lambda.

Differential Scanning calorimetry (DSC) analysis were performed by usinga Thass DSC-XP-10 instrument under atmospheric conditions.

UV-Vis spectra were recorded using a Perkin Elmer Lambda 20spectrophotometer. Photoluminescence spectra were collected on a PerkinElmer LS50 spectrofluorometer.

EXAMPLE 1 Synthesis of(E)-2,2′-(5,5′-(ethene-1,2-diyl)bis(thiophene-5,2-diyl))bis(5-hexyl-4H-thieno[2,3-c]pyrrole-4,6(5H)-dione,compound 1 Step (a)

2-(5-bromothiophen-2-yl)-5-hexyl-4H-thieno[2,3-c]pyrrole-4,6(5H)-dionewas prepared from commercially available thiophene-2,3-dicarboxylic acidfollowing the procedure described in M. Melucci, M. Zambianchi, L.Favaretto, M. Gazzano, A. Zanelli, M. Monari, R. Capelli, S. Troisi, S.Toffanin, M. Muccini, Chem. Commun. 2011, 47, 11840 by using n-hexylamine instead of n-butyhilamine in the same molar ratio.

Step (b)

To a refluxing toluene solution (8 ml) of2-(5-bromothiophen-2-yl)-5-hexyl-4H-thieno[2,3-c]pyrrole-4,6(5H)-dione(175 mg, 0.44 mmol) and in-situ prepared catalyst Pd(AsPh₃)₄ (10 mol %,i.e. 11 mg of Pd₂dba₃ and 26 mg of AsPh₃) under N₂ atmosphere,commercially available trans-1,2-bis(tributylstannyl)ethene (153 mg,0.20 mmol) in toluene (3 ml), was added drop wise. The solution wasrefluxed for 24 h then the solvent was removed under vacuum, and thecrude product was washed with pentane. The residue was purified by flashchromatography performed on a automated system (CombiFlash® Rf 200,Teledyne-Isco, Lincoln, Nebr., USA) using a 4-gram silica RediSep columnand cyclohexane-ethyl acetate solvent gradients. The fractionscontaining the product were combined, the solvent evaporated, and theresidue crystallized from hot toluene to give a dark red solid (81 mg,58%). M.p. 255° C., MS (70 eV, EI): m/z 662 (M.⁻¹), absorption maximum,465 nm, emission maximum, 588 nm in DCM; ¹H NMR (CDCl₃, TMS/ppm) δ 7.31(s, 2H), 7.24 (d, ³J=4.0 Hz, 2H), 7.04 (d, ³J=4.0 Hz, 2H), 7.02 (s, 2H),3.60 (t, 4H), 1.64 (m, 4H), 1.31 (m, 12H), 0.88 (m, 6H); ¹³C NMR (CDCl₃,TMS/ppm) δ 163.9, 162.7, 149.8, 145.2, 143.6, 137.3, 134.3, 128.0,126.6, 122.0, 116.4, 38.6, 31.4, 28.8, 26.5, 22.5, 14.0. Anal. Calcd forC₃₄H₃₄N₂O₄S₄ (662.90): C, 61.60; H, 5.17. Found: C, 61.54; H, 5.22.

FIG. 1 shows the UV-vis and emission spectra of compound 1 in CH₂Cl₂.

The DSC thermograms of compound 1 (second run, 25° C./min) in air areshown in FIGS. 3 (a) and (b).

The heating curve (FIG. 2a ) shows a first transition located at about220° C. corresponding to the melting of the crystalline phase to theliquid crystalline phase and a second transition corresponding to theclearing point at about 240° C. On cooling the melt (FIG. 2b ), atransition was observed at about 190° C. and corresponds to there-crystallization of the melt.

In polarized microscopy images, the liquid crystalline mesophases wereobserved between 240° C. and 242° C. when heating a compound 1 powdersample.

EXAMPLE 2 Fabrication and Optoelectronic Measurements of Thin FilmTransistor (OTFT)

Organic thin film transistors were fabricated in bottom gate-top contactgeometry. An ITO substrate was cleaned be means of two sonicationcycles, first in acetone and then 2-isopropanol, for 10 minutes each.Then a 450 nm thick dielectric layer of PMMA was grown by spin-coatingon top of the clean ITO substrate. The relative electric permittivity εwas 3.6 at 100 Hz. The PMMA layer was then thermally annealed in a glovebox at 120° C. (i.e., around 10° C. above the glass transitiontemperature for PMMA) for 15 hours under inert atmosphere. (CPMMA=7.08nF/cm²).

Then, an organic thin film layer consisting of compound 1 was grown onthe top of said dielectric layer by vacuum sublimation in a vacuumchamber, with a deposition rate of 0.03 Å/s, at a base pressure of 10⁻⁶mbar. The substrate temperature during the film deposition was kept atroom temperature (RT).

Then, gold drain and source electrodes were made on top of the organicthin film by evaporation through a shadow mask. The thickness of saidgold drain and source electrodes was 50 nm, while the channel length (L)and the channel width (W) were 40 μm and 12 mm, respectively.

The electrical characteristics of such a transistor were then measured.All optoelectronic measurements were carried out in an MBraun nitrogenglove box using a standard SUSS Probe Station.

The mobility values in saturation were calculated from the locus curvesusing the standard equations:μ=L/(W*C)A^2  [eq. 1]

wherein A is the angular coefficient of the line fitting the square rootof the drain current vs the applied voltage, L is the channel length, Wthe channel width and C is the transistor dielectric capacitance.

FIG. 3 (a) shows the locus curve N, and FIG. 3(b) the type output curveof such transistor comprising an organic layer consisting of compound 1.

FIG. 4 shows the transfer saturation curve N Type of such transistorcomprising an organic layer consisting of compound 1, with μ_(N)=2 10⁻³cm²/Vs, V_(T) ^(N)≈60V.

FIG. 5 shows the transfer saturation curve P Type of such transistorcomprising an organic layer consisting of compound 1, with μ_(P)=1 10⁻⁷cm²V/s, V_(T) ^(P)≈70V.

EXAMPLE 3 Synthesis of2,2′-(5,5′-(Ethyne-1,2-diyl)bis(thiophene-5,2-diyl))bis(5-hexyl-4H-thieno[2,3-c]pyrrole-4,6(5H)-dione),compound 7

Step a): Synthesis of 2,2′-Bithienylacethylene

A dry round-bottom flask was charged with PdCl₂(PPh₃)₂ (210 mg, 6 mol%), CuI (190 mg, 10 mol %), and 2-iodothiophene, (1.02 ml, 0.01 mol).Dry benzene (50 ml) was added under stirring. Argon-sparged DBU (8.97ml, 0.06 mol) was added by syringe and the reaction flask was purgedwith argon. Ice-chilled trimethylsilylethynylene (0.69 ml, 5 mmol) wasadded by syringe, immediately followed by distilled water (73 μL, 4mmol). The reaction was carried out in absence of light for 18 h at roomtemperature. The reaction mixture was then partitioned in ethyl etherand distilled water (200 ml each). The organic layer was washed with aqHCl (10% w/w, 3×250 ml) and brine (1×250 ml), dried over Na₂SO₄ andconcentrated under reduced pressure. Purification of the crude byflash-chromatography on silica gel (elution with n-hexane) gave the pureproduct 2,2′-bithienylacethylene as a white crystalline solid. Yield=72%(984 mg). M.p. 101° C. (lit. 96° C.). ELMS m/z 190 (M⁺). ¹H NMR (CDCl₃,TMS/ppm) δ 7.31 (dd, ³J=5.2 Hz, ⁴J=1.2 Hz, 2H), 7.28 (dd, ³J=3.6 Hz,⁴J=1.2 Hz, 2H), 7.02 (dd, ³J=5.2 Hz, ³J=3.6 Hz, 2H); ¹³C NMR (CDCl₃,TMS/ppm) δ 132.1, 127.6, 127.1, 122.9, 86.2.

Step b): Synthesis of 5,5′-Bis(tributylstannyl)-2,2′-bithienylacetylene

To a solution of 2,2′-bithienylacethylene (190 mg, 1.00 mmol) in dryethyl ether (12 mL) n-BuLi (2.5 M in hexane, 0.92 ml, 2.30 mmol) wasadded at room temperature. After 1 h, tributyltin chloride (0.57 ml,2.10 mmol) was added dropwise. The reaction mixture was left understirring at room temperature for 4 h, then partitioned in AcOEt anddistilled water (50 ml each). The organic layer was washed with brine(2×50 ml), dried over Na₂SO₄ and concentrated. The title compound wasobtained in quantitative yield as a yellow-amber oil and used withoutfurther purification for the final synthetic step. EI-MS m/z 768 (M⁺).¹H NMR (CDCl₃, TMS/ppm) δ 7.36 (d, ³J=3.2 Hz, 2H), 7.05 (d, ³J=3.2 Hz,2H), 1.55 (m, 12H), 1.33 (m, 12H), 1.12 (m, 12H), 0.91 (m, 18H).

Step c): Synthesis of2,2′-(5,5′-(Ethyne-1,2-diyl)bis(thiophene-5,2-diyl))bis(5-hexyl-4H-thieno[2,3-c]pyrrole-4,6(5H)-dione),compound 7

To a refluxing toluene solution (15 ml) of2-bromo-5-hexyl-4H-thieno[2,3-c]pyrrole-4,6(5H)-dione, 4 (348 mg, 1.10mmol) and in-situ prepared catalyst Pd(AsPh₃)₄ (10 mol %, i.e. 52 mg ofPd₂dba₃ and 122 mg of AsPh₃) under N₂ atmosphere, compound 3 (384 mg,0.50 mmol) was added dropwise. The solution was refluxed for 24 h, thenthe solvent was removed under vacuum, and the crude product was washedwith pentane. The residue was purified by flash chromatography performedon a automated system (CombiFlash® Rf 200, Teledyne-Isco, Lincoln,Nebr., USA) with a 24-gram silica RediSep column and cyclohexane-ethylacetate solvent gradients.

Due to its strong retention on silica gel, the title compound wasfinally eluted with hot toluene. The fractions containing the productwere combined, the solvent evaporated, and the residue crystallized fromtoluene giving 225 mg of orange solid (68% yield). M.p. 228° C. EI-MSm/z 660 (M⁺). λ_(max) (CH₂Cl₂), 433 nm, λ_(em) (CH₂Cl₂), 547 nm. ¹H NMR(CDCl₃, TMS/ppm) δ 7.34 (s, 2H), 7.25 (d, ³J=4.0 Hz, 2H), 7.24 (d,³J=4.0 Hz, 2H), 3.60 (t, 4H), 1.62 (m, 4H), 1.31 (m, 12H), 0.88 (m, 6H).¹³C NMR (CDCl₃, TMS/ppm) δ 163.8, 162.6, 148.9, 145.2, 138.1, 137.1,133.5, 125.9, 124.0, 117.1, 88.1, 38.7, 31.4, 28.7, 26.5, 22.5, 14.0.Anal. Calcd for C₃₄H₃₂N₂O₄S₄ (660.89): C, 61.79; H, 4.88. Found: C,61.72; H, 4.95.

EXAMPLE 4 Synthesis of(E)-2,2′-(5′,5′″-(ethene-1,2-diyl)bis([2,2′-bithiophene]-5′,5-diyl))bis(5-hexyl-4H-thieno[2,3-c]pyrrole-4,6(5H)-dione),compound 8

Step a): Synthesis of(E)-1,2-bis(5-(tributylstannyl)thiophen-2-yl)ethane

To an anhydrous solution of (E)-1,2-bis(2-thienyl)ethane^(ref 1) (0.900g, 0.00469 mol) in 25 ml of THF under nitrogen atmosphere, TMEDA(Tetramethylethylenediamine) (0.0103 mol) was added at −50° C. Then, thesolution was refrigerated at −78° C. and BuLi (2.5 M in hexane) (4.3 ml,0.01078 mol) was added dropwise. The mixture was stirred for 30 minutesthen refluxed for 1 hour and refrigerated at −78° C. At this temperatureBu₃SnCl (3.2 g, 0.0098 mol) was added dropwise and the reaction mixturewas stirred overnight at room temperature. The solvent was removed undervacuum, then the mixture was dissolved in CH₂Cl₂ and quenched withwater. After extraction, the organic phase was dried over Na₂SO₄ and thesolvent was evaporated, obtaining the desired compound as a brown oil(3.5 g, yield 98%).

EI-MS m/z 770 (M.⁺).

¹H NMR (CDCl₃, TMS/ppm) δ 7.12 (d, ³J=3.6 Hz, 2H), 7.10 (s, 2H), 7.04(d, ³J=3.2 Hz, 2H), 1.56 (m, 6H), 1.32 (m, 6H), 1.10 (m, 6H), 0.91 (t,9H).

¹³C NMR (CDCl₃, TMS/ppm) δ 148.2, 136.7, 136.0, 126.9, 121.1, 28.9,27.3, 13.7, 10.8.

Ref 1: Heteroatom Chemistry, vol 14, n 3, 2003, 218.

Step b): Synthesis of(E)-2,2′-(5′,5′″-(ethene-1,2-diyl)bis([2,2′-bithiophene]-5′,5-diyl))bis(5-hexyl-4H-thieno[2,3-c]pyrrole-4,6(5H)-dione),compound 8

To a refluxing toluene solution (5 ml) of the compound obtained in stepa) (163 mg, 0.41 mmol) and in-situ prepared catalyst Pd(AsPh₃)₄ (10 mol%, i.e. 21 mg of Pd₂dba₃ and 49 mg of AsPh₃ in 12 ml toluene) under N₂atmosphere, 2 (145 mg, 0.188 mmol) in toluene (1.5 ml), was addeddropwise. The solution was refluxed for 7 h then, at room temperature,pentane was added. The solid obtained by removing the solvents waspurified by flash chromatography on silica gel (elution with pentane:CH₂Cl₂: AcOEt/40:30:30→pentane: CH₂Cl₂/70:30→CH₂Cl₂). The fractionscontaining the product were combined, the solvent evaporated, and theresidue crystallized from hot toluene to give a dark red solid (65 mg,yield 42%).

M.p. 286° C. EI-MS m/z 826 (M.⁺). λ_(max) (CH₂Cl₂), 487 nm, λ_(em)(CH₂Cl₂), 626 nm. ¹H NMR (CDCl₃, TMS/ppm) δ 7.31 (s, 2H), 7.25 (d,³J=3.6 Hz, 2H), 7.14 (d, ³J=4.0 Hz, 2H), 7.13 (d, ³J=3.6 Hz, 2H), 6.99(d, ³J=4.0 Hz, 2H), 6.98 (s, 2H), 3.60 (t, 4H), 1.64 (m, 4H), 1.31 (m,12H), 0.88 (t, 6H).

The invention claimed is:
 1. A compound having formula (II):

wherein: R¹, R², R³ independently of each other, are selected from agroup consisting of C₁-C₆ linear alkyl groups, C₆ cycloalkyl groups, andC₆ unsubstituted and substituted monocyclic aryl groups; R⁴ and R⁵,independently of each other, are selected from a group consisting ofhydrogen, and C₁ alkyl group, Ar¹, Ar², Ar³ and Ar⁴, independently ofeach other, are moieties selected from a group consisting of a C₆unsubstituted and substituted monocyclic aryl groups, C₄ unsubstitutedand substituted monocyclic heteroaryl groups, and C₆ unsubstituted andsubstituted polycyclic heteroaryl groups or combinations thereof asdimers, trimers and tetramers; Z and Z′, independently of each other,are selected from a group consisting of bivalent radicals of formulas(III), (IV), (V), and (VI):

wherein G is selected from a group consisting of hydrogen, halogens,C₁-C₂₀ linear or branched alkyl groups, C₂-C₂₀ linear or branchedalkenyl groups, C₂-C₂₀ linear or branched alkynyl groups, C₁-C₂₀ linearor branched heteroalkyl groups, C₂-C₂₀ linear or branched heteroalkenylgroups, C₂-C₂₀ linear or branched heteroalkynyl groups, C₃-C₂₀ linear orbranched cycloalkyl groups, C₃-C₂₀ linear or branched heterocycloalkylgroups, C₂-C₂₀ linear or branched alkylcarboxylic groups, C₂-C₂₀ linearor branched alkylcarboxamide groups, C₂-C₂₀ linear or branchedalkylimino groups, C₁-C₂₀ linear or branched alkylsulphonic groups,C₁-C₂₀ linear or branched nitrile groups, C₆-C₅₀ unsubstituted andsubstituted monocyclic aryl groups, C₁₀-C₅₀ polycyclic aryl groups,C₁₀-C₅₀ substituted polycyclic aryl groups, C₁-C₅₀ unsubstituted andsubstituted monocyclic heteroaryl groups, C₆-C₅₀ polycyclic heteroarylgroups, and C₆-C₅₀ substituted polycyclic heteroaryl groups orcombinations thereof; s is 0 or 1; n, m, r and t, independently of eachother, are integers between 1 and 50; q and f, independently of eachother, are integers between 1 and 10; and p is
 0. 2. The compoundaccording to claim 1, having formula (IIa):

wherein R¹, R², R⁴, R⁵, Ar¹, Ar⁴, Z, f, n, m are as specified inclaim
 1. 3. The compound according to claim 1, wherein q and f are each1 or 2, and n, and m are between 2 and
 10. 4. The compound according toclaim 1, wherein Z′ and/or Z are selected from a group consisting ofethynylene, cis-ethenylene and trans-ethenylene.
 5. The compoundaccording to claim 1, wherein Ar¹, Ar², Ar³ and/or Ar⁴, independently ofeach other, are selected from a group consisting of the following units(a), (b), (c), (d), (e), (f), (g), (h), (i), (l), (m), (n), (o), (p),(q), and (r):

wherein A is selected from a group consisting of S, O, Se, atoms and SO,SO₂, R¹⁴—P═O, P—R¹⁴, N—R¹⁵, Si(R¹⁵)₂) groups; D is selected from a groupconsisting of C, S, O Se, atoms and SO, SO₂, R¹⁴—P═O, P—R¹⁴, BR¹⁴,N—R¹⁵, Si(R¹⁵)₂ groups; B, C, independently of each other, are selectedfrom a group consisting of C, N atoms; E is selected from a groupconsisting of C(R¹⁵)₂, S, O, and NR¹⁵ group; R⁸, R⁹, R¹⁰, R¹¹, R¹² andR¹³, independently of each other, are selected from a group consistingof hydrogen, halogens, C₁-C₂₀ linear or branched alkyl groups, C₂-C₂₀linear or branched alkenyl groups, C₂-C₂₀ linear or branched alkynylgroups, C₁-C₂₀ linear or branched heteroalkyl groups, C₂-C₂₀ linear orbranched heteroalkenyl groups, C₂-C₂₀ linear or branched heteroalkynylgroups, C₃-C₂₀ linear or branched cycloalkyl groups, C₂-C₂₀ linear orbranched heterocycloalkyl groups, C₂-C₂₀ linear or branchedalkylcarboxylic groups, C₂-C₂₀ linear or branched alkylcarboxamidegroups, C₂-C₂₀ linear or branched alkylimino groups, C₁-C₂₀ linear orbranched alkylsulphonic groups, C₁-C₂₀ linear or branched nitrilegroups, and C₅-C₄₀ aryl groups, C₆-C₄₀ alkylaryl groups; R¹⁴, R¹⁵independently of each other, are selected from a group consisting ofhydrogen, C₁-C₂₀ linear or branched alkyl groups, C₂-C₂₀ linear orbranched alkenyl groups, C₂-C₂₀ linear or branched alkynyl groups,C₁-C₂₀ linear or branched heteroalkyl groups, C₂-C₂₀ linear or branchedheteroalkenyl groups, C₂-C₂₀ linear or branched heteroalkynyl groups,C₃-C₂₀ linear or branched cycloalkyl groups, C₃-C₂₀ linear or branchedheterocycloalkyl groups, C₂-C₂₀ linear or branched alkylcarboxylicgroups, C₂-C₂₀ linear or branched alkylcarboxamide groups, C₂-C₂₀ linearor branched alkylimino groups, C₁-C₂₀ linear or branched alkylsulphonicgroups, C₁-C₂₀ linear or branched nitrile groups, C₅-C₄₀ aryl groups,and C₆-C₄₀ alkylaryl groups.
 6. The compound according to claim 1,wherein Ar¹, Ar², Ar³ and/or Ar⁴, independently of each other, areselected from a group consisting of the following groups (s) and (t):

wherein A is selected from a group consisting of S, O, Se, atoms and SO,SO₂, R¹⁴—P═O, P—R¹⁴, N—R¹⁵, Si(R¹⁵)² groups; W is a moiety selected froma group consisting of the units (a), (b), (c), (d), (e), (f), (g), (h),(i), (l), (m), (n), (o), (p), (q), and (r) of claim 5; and R¹⁶ isselected from a group consisting of hydrogen, halogens, C₁-C₂₀ linear orbranched alkyl groups, C₂-C₂₀ linear or branched alkenyl groups, C₂-C₂₀linear or branched alkynyl groups, C₁-C₂₀ linear or branched heteroalkylgroups, C₂-C₂₀ linear or branched heteroalkenyl groups, C₂-C₂₀ linear orbranched heteroalkynyl groups, C₃-C₂₀ linear or branched cycloalkylgroups, C₃-C₂₀ linear or branched heterocycloalkyl groups, C₁-C₂₀ linearor branched alkylcarboxylic groups, C₁-C₂₀ linear or branchedalkylcarboxamide groups, C₁-C₂₀ linear or branched alkylimino groups,C₁-C₂₀ linear or branched alkylsulphonic groups, C₁-C₂₀ linear orbranched nitrile groups, C₅-C₄₀ aryl groups, and C₆-C₄₀ alkylarylgroups.
 7. The compound according to claim 1, wherein Ar¹, Ar², Ar³and/or Ar⁴, independently of each other, are selected from a groupconsisting of the following formulas (u), (v), (w), (x) and (y):

wherein n is comprised between 2 and 10 and R⁸, R⁹, independently ofeach other, are selected from a group consisting of hydrogen, halogens,C₁-C₂₀ linear or branched alkyl groups, C₂-C₂₀ linear or branchedalkenyl groups, C₂-C₂₀ linear or branched alkynyl groups, C₁-C₂₀ linearor branched heteroalkyl groups, C₂-C₂₀ linear or branched heteroalkenylgroups, C₂-C₂₀ linear or branched heteroalkynyl groups, C₃-C₂₀ linear orbranched cycloalkyl groups, C₂-C₂₀ linear or branched heterocycloalkylgroups, C₂-C₂₀ linear or branched alkylcarboxylic groups, C₂-C₂₀ linearor branched alkylcarboxamide groups, C₂-C₂₀ linear or branchedalkylimino groups, C₁-C₂₀ linear or branched alkylsulphonic groups,C₁-C₂₀ linear or branched nitrile groups, C₅-C₄₀ aryl groups, and C₆-C₄₀alkylaryl groups.
 8. A compound having the following formula:


9. An organic semiconductor material in an electronic device comprisingthe compound according to claim
 1. 10. The organic semiconductormaterial in the electronic device according to claim 9, wherein theorganic semiconductor material is an n-type organic semiconductormaterial.
 11. An electronic device comprising a semiconductor layer incontact with a number of electrodes, wherein the semiconductor layerincludes at least one compound according to claim
 1. 12. A compoundhaving formula (I):

wherein: R¹, R², R³ independently of each other, are selected from agroup consisting of C₁-C₆ linear alkyl groups, C₆ cycloalkyl groups, andC₆ unsubstituted and substituted monocyclic aryl groups; Ar, Ar¹, Ar²,Ar³ and Ar⁴, independently of each other, are moieties selected from agroup consisting of a C₆ unsubstituted and substituted monocyclic arylgroups, C₄ unsubstituted and substituted monocyclic heteroaryl groups,and C₆ unsubstituted and substituted polycyclic heteroaryl groups orcombinations thereof as dimers, trimers and tetramers; Z and Z′,independently of each other, are selected from a group consisting ofbivalent radicals of formulas (III), (IV), (V), and (VI):

wherein G is selected from a group consisting of hydrogen, halogens,C₁-C₂₀ linear or branched alkyl groups, C₂-C₂₀ linear or branchedalkenyl groups, C₂-C₂₀ linear or branched alkynyl groups, C₁-C₂₀ linearor branched heteroalkyl groups, C₂-C₂₀ linear or branched heteroalkenylgroups, C₂-C₂₀ linear or branched heteroalkynyl groups, C₃-C₂₀ linear orbranched cycloalkyl groups, C₃-C₂₀ linear or branched heterocycloalkylgroups, C₂-C₂₀ linear or branched alkylcarboxylic groups, C₂-C₂₀ linearor branched alkylcarboxamide groups, C₂-C₂₀ linear or branchedalkylimino groups, C₁-C₂₀ linear or branched alkylsulphonic groups,C₁-C₂₀ linear or branched nitrile groups, C₆-C₅₀ unsubstituted andsubstituted monocyclic aryl groups, C₁₀-C₅₀ polycyclic aryl groups,C₁₀-C₅₀ substituted polycyclic aryl groups, C₁-C₅₀ unsubstituted andsubstituted monocyclic heteroaryl groups, C₆-C₅₀ polycyclic heteroarylgroups, and C₆-C₅₀ substituted polycyclic heteroaryl groups orcombinations thereof; s is 0 or 1; n, m, r and t, independently of eachother, are integers between 1 and 50; q and f, independently of eachother, are integers between 1 and 10; and p is
 0. 13. The compoundaccording to claim 12, having formula (Ia):

wherein R¹, R², Ar, Ar¹, Ar⁴, Z, f, n, m are as specified in claim 12.14. The compound according to claim 12, wherein q and f are each 1 or 2,and n, and m are between 2 and
 10. 15. The compound according to claim12, wherein Z′ and/or Z are selected from a group consisting ofethynylene, cis-ethenylene and trans-ethenylene.